Den 18.01.2018 13.07, skrev Meghana Madhyastha:
On Tue, Jan 16, 2018 at 06:08:53PM +0100, Noralf Trønnes wrote:
Den 16.01.2018 11.36, skrev Meghana Madhyastha:
Replace of_find_backlight_by_node and of the code around it
with of_find_backlight helper to avoid repetition of code.
Signed-off-by: Meghana Madhyastha <meghana.madhyas...@gmail.com>
---
drivers/gpu/drm/panel/panel-innolux-p079zca.c | 10 +++-------
drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c | 10 +++-------
drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c | 10 +++-------
3 files changed, 9 insertions(+), 21 deletions(-)
diff --git a/drivers/gpu/drm/panel/panel-innolux-p079zca.c
b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
index 4c1b29eec..a69b0530f 100644
--- a/drivers/gpu/drm/panel/panel-innolux-p079zca.c
+++ b/drivers/gpu/drm/panel/panel-innolux-p079zca.c
@@ -230,14 +230,10 @@ static int innolux_panel_add(struct innolux_panel
*innolux)
innolux->enable_gpio = NULL;
}
- np = of_parse_phandle(dev->of_node, "backlight", 0);
- if (np) {
- innolux->backlight = of_find_backlight_by_node(np);
- of_node_put(np);
+ innolux->backlight = devm_of_find_backlight(np);
This driver isn't broken like tinydrm was, so it does put the backlight
device on cleanup like it should. So when you're using the devm_ version,
the result is a double put. Just remove the put_device() in
innolux_panel_add/del() and you're good.
I have a quick question here. So devm_of_find_backlight automatically
does a put_device on detachment of the driver. However in this case,
put_device is called when panel_add is not successful (i.e when it
returns a negative value here). So is devm's release mechanism still
invoked here ?
As long as the error is propagated back up the chain, which it is in this
case, devres_release_all() is called and the resources are released.
Driver callchain passing up the error:
innolux_panel_driver.probe = innolux_panel_probe <- innolux_panel_add <-
devm_of_find_backlight
This is mipi_dsi setting up the probe hook and calling into it's own
version:
drivers/gpu/drm/drm_mipi_dsi.c:
int mipi_dsi_driver_register_full(struct mipi_dsi_driver *drv,
struct module *owner)
{
...
if (drv->probe)
drv->driver.probe = mipi_dsi_drv_probe;
...
}
static int mipi_dsi_drv_probe(struct device *dev)
{
struct mipi_dsi_driver *drv = to_mipi_dsi_driver(dev->driver);
struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
return drv->probe(dsi);
}
This is the device-driver core that initiates the probing:
drivers/base/dd.c
static int really_probe(struct device *dev, struct device_driver *drv)
{
...
} else if (drv->probe) {
ret = drv->probe(dev);
if (ret)
goto probe_failed;
}
...
probe_failed:
...
devres_release_all(dev);
...
}
err = drm_panel_add(&innolux->base);
if (err < 0)
goto put_backlight;
return 0;
put_backlight:
put_device(&innolux->backlight->dev);
return err;
If so then I should change this to
err = drm_panel_add(&innolux->base)
return err;
Yes, and you can drop the variable:
return drm_panel_add(&innolux->base);
Noralf.
Thanks and regards,
Meghana
I haven't checked the other drivers.
Noralf.
PS:
Give people a few days (one week?) to respond before respinning a new
version, so we avoid a fragmented discussion.
- if (!innolux->backlight)
- return -EPROBE_DEFER;
- }
+ if (IS_ERR(innolux->backlight))
+ return PTR_ERR(innolux->backlight);
drm_panel_init(&innolux->base);
innolux->base.funcs = &innolux_panel_funcs;
diff --git a/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
b/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
index 1512ec4f3..d5450c9d9 100644
--- a/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
+++ b/drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c
@@ -329,14 +329,10 @@ static int sharp_panel_add(struct sharp_panel *sharp)
if (IS_ERR(sharp->supply))
return PTR_ERR(sharp->supply);
- np = of_parse_phandle(sharp->link1->dev.of_node, "backlight", 0);
- if (np) {
- sharp->backlight = of_find_backlight_by_node(np);
- of_node_put(np);
+ sharp->backlight = devm_of_find_backlight(np);
- if (!sharp->backlight)
- return -EPROBE_DEFER;
- }
+ if (IS_ERR(sharp->backlight))
+ return PTR_ERR(sharp->backlight);
drm_panel_init(&sharp->base);
sharp->base.funcs = &sharp_panel_funcs;
diff --git a/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
b/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
index a6af3257f..db31d8268 100644
--- a/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
+++ b/drivers/gpu/drm/panel/panel-sharp-ls043t1le01.c
@@ -273,14 +273,10 @@ static int sharp_nt_panel_add(struct sharp_nt_panel
*sharp_nt)
gpiod_set_value(sharp_nt->reset_gpio, 0);
}
- np = of_parse_phandle(dev->of_node, "backlight", 0);
- if (np) {
- sharp_nt->backlight = of_find_backlight_by_node(np);
- of_node_put(np);
+ sharp_nt->backlight = devm_of_find_backlight(np);
- if (!sharp_nt->backlight)
- return -EPROBE_DEFER;
- }
+ if (IS_ERR(sharp_nt->backlight))
+ return PTR_ERR(sharp_nt->backlight);
drm_panel_init(&sharp_nt->base);
sharp_nt->base.funcs = &sharp_nt_panel_funcs;
